The present invention relates generally to injection molding machines and processes and, more particularly, to nozzle apparati and methods for mounting nozzles in sealable alignment with the gate(s) to mold cavity(ies). Injection molding machines may utilize heated manifolds or hot runners to distribute the flow of molten plastic to one or more nozzles. The flow path communication between the hot runners and the nozzle and between the end of the nozzle and the gate to the mold cavity is preferably tightly sealed via compressed contact between the mating surfaces of the hot runner/nozzle and nozzle/gate in order to prevent leakage of plastic, gases and the like which are flowing through the hot runner and nozzle under high pressure. Where a single hot runner or manifold is used to deliver plastic flow to more than one nozzle, the mating surfaces of the hot runner and the nozzles and the mounting of the nozzles must be precisely machined/designed in order to provide the desired compression contact for each individual nozzle particularly where the individual components, such as the manifold, nozzle and associated component(s) (e.g. the mold housing itself or a retainer plate which may be mounted on the mold) expand when heated from their cold (room temperature) state to their machine operating state. As can be readily imagined, it can be difficult and expensive to manufacture a manifold, nozzle and mounting housing(s) which highly precisely effect the desired amount of compression and alignment between the manifold/nozzle and nozzle/gate surfaces at the elevated operating temperature of the machine.